龄期和替代率对复合粗骨料再生混凝土强度的影响

INFLUENCE OF AGE AND SUBSTITUTION RATE ON STRENGTH OF COMPOUND COARSE AGGREGATE RECYCLED CONCRETE

随着养护龄期的增长，再生混凝土的强度基本呈线性关系递增；再生粘土砖混凝土替代率为40％～80％时，强度折减一级；当粗骨料全部被粘土砖取代时，再生粘土砖混凝土强度等级仅为C30；再生废弃混凝土骨料的混凝土替代率为20％时强度最高，废弃混凝土占粗骨料的80％时，强度最低；再生粘土砖、废弃混凝土骨料的混凝土替代率和强度基本符合线性递减关系。最优骨料类型为20％替代率的再生废弃混凝土。

With the age growing, strength of recycled concrete increases linearly.The strength degrades one level if the substitution rate is between 40% and 80%, and decline to C30 level with 100% substitution rate. The strength of concrete with abandoned concrete is at its best in 100% substitution rate while is at its worst in 80% substitution rate. Basically, strength of concrete with recycled clay brick and abandoned concrete decreases to substitution rate linearly. The best coarse type is recycled abandoned concrete with 20% substitution rate.